Beautiful! I just bought my first complex Paph and was shocked at how large the blooms are. Anything special I should know about its culture?

I can't really think of any special treatment for these. I give mine intermediate temperatures, bright indirect light (equivalent to an east window), let medium slightly dry between waterings, and fertilizer lightly year round. My biggest issue has been allowing some of my complex paphiopedilums to get too dry between water specially in the summer. But that is a problem I struggle with across the collection. I can think of a plant i lodt to over watering. Oh...Also I give the more shade in the summer when temperatures creep into the 80s.

Your medium looks like sphagnum, but I can also see sponge rock? Is the sphagnum just top dressing?

The medium is a mix of coconut husk, sponge rock, and charcoal. You are right on the sphagnum. It is just a top dressing. This one has done very well in the husk base medium. Others did not do as well. I am not sure why though. I will likely change back to bark for it when repotting time comes along.